A touch panel is known which comprises two resistive films laid on top of each other with a gap between the films. Each of the resistive films comprises terminals on the respective opposite end sides thereof. The two resistive films overlap so that the terminals of one of the films are orthogonal to the terminals of the other film. When a user's touch allows the resistive films to come into contact with each other, terminal voltages change. Based on these terminal voltages, the input coordinates of the single point at which the touch panel has been touched can be calculated.
Furthermore, when the panel is touched at two points, the resistance between the terminals decreases. Thus, whether the panel is touched at one or two points can be determined based on the change in resistance. Moreover, if the panel is determined to be touched at two points, the distance between the two points can be calculated based on the change in resistance.
On the other hand, no technique has been known which allows calculation of the input coordinates of two points at which a resistive touch panel is touched. The calculated input, coordinates of the two points can be utilized as significant input information.